The present invention relates to a container case for a magnetic tape cassette, and more particularly to an improved magnetic tape cassette container case used for storage of an audio magnetic tape cassette.
A magnetic tape cassette for audio recording and/or reproducing purposes or the like is usually placed in a magnetic tape cassette container case for storage when it is not in use.
Such magnetic tape cassettes have cassette front openings into which magnetic heads are inserted when the cassette is loaded into a recording/reproducing device, and a magnetic tape in the cassette is caused to run across these front openings. However, foreign matter such as dust or fine particles tend to intrude into the cassette through the front openings, and when such a dust deposits on the magnetic tape, signal drop-out can develop so that the high quality of recording and reproducing can no longer be achieved. Further, because the housing of the cassette is molded of a synthetic resin, the cassette is prone to breakage by an impact produced, for example, when the cassette is dropped.
In order to prevent dust from depositing on the magnetic tape and also to protect the whole of the cassette, the cassette is contained in the container case.
Referring to a basic construction of the container case, the container case includes a lid member having a pocket for receiving the thick portions of the cassette, and the lid member pivotally connected to a casing member so that it can be opened and closed like a door. Each of the lid member and the casing member is integrally molded of a synthetic resin.
When the cassette is to be stored in the container case, the thick portions, in which the front openings are formed, are inserted into the pocket, and then the lid member and the casing member are closed together. As a result, the whole of the cassette is contained in the container case, and thus can be stored a dust-preventing, impact-resistant manner.
The appearance or external shape of a cassette 11 of a type presently in extensive use will now be described with reference to FIG. 7. As shown therein, the cassette is flat as a whole, with thick portions 12 formed on opposite faces adjacent to the front openings of the cassette. Shaft insertion holes 13 through which pass respective shafts for driving the magnetic tape wound on hubs also are formed in the opposite faces of the cassette. External guide portions 14 in the form of an elongated projection are formed on each of right and left side walls of the cassette 11, these external guide portions 14 being used when loading the cassette 11 into a tape recorder or the like.
The thick portions 12 and the external guide portions 14 must be standardized for purposes of making the cassette interchangeable, and hence cannot be omitted. Therefore, the inner dimensions of the pocket of the container case must be determined so as to receive both the thick portions 12 and the external guide portions 14, and some gaps for insertion and withdrawal purposes are also required, Therefore, it is inevitable to make the outer dimensions of the container case longer than that of the outer dimensions of the cassette, adding at least the thickness of the walls of the container case per se, and the gaps.
On the other hand, the magnetic tape cassette is often used in an automobile, and is also taken out and used outdoors. In view of such use, if the container case is of a large size, a large amount of storage space is required in an automobile or the like, and a large size is also inconvenient from the viewpoint of portability. Therefore, it has been desired to provide a small-sized and thin cassette.
Further, although the container case of the above construction receives the thick portions in its pocket, it has no means for snugly fitting or retaining the cassette relative to the case, and therefore the cassette can rattle within the container case when carrying the container case.